A reappraisal of the mechanisms underlying the cardiac complications of sickle cell anemia

Prevalence of Cardiovascular Complications in Individuals with Sickle Cell Anemia and Other Hemoglobinopathies: A Systematic Review

BACKGROUND

Sickle cell anemia (SCA) is a hereditary disease whose cardiovascular complications are the main cause of death, the same being observed in other hemoglobinopathies. Early identification of these changes can favorably modify the course of the disease.

OBJECTIVE

To compare the prevalence of cardiovascular complications between individuals with SCA and individuals with other hemoglobinopathies.

METHOD

Following the recommendations of the PRISMA protocol, a systematic literature review was carried out with searches in PubMed/Medline databases, associated with a manual search. Studies that analyzed the prevalence of cardiovascular alterations in hemoglobinopathies (SCA, sickle cell trait, SC hemoglobinopathy, alpha-thalassemia and beta-thalassemia) were included. The methodological quality of the articles was assessed using the Newcastle-Ottawa scale.

RESULTS

Four studies were selected for analysis, resulting in a sample size of 582 participants: 289 with SCA, 133 with SC hemoglobinopathy, 40 with beta-thalassemia, 100 healthy individuals and none with alpha-thalassemia or sickle cell trait. Dilatation of the cardiac chambers, left and right ventricular hypertrophy, pulmonary hypertension, diastolic dysfunction, mitral regurgitation and tricuspid regurgitation are more prevalent in SCA than in the other hemoglobinopathies considered. Myocardial iron overload is more frequent in thalassemia major than in sickle cell anemia. Systolic function is similar between different hemoglobinopathies.

CONCLUSION

There is greater cardiovascular impairment in individuals with SCA than in those with other hemoglobinopathies, reinforcing the necessity for regular cardiovascular follow-up in sickle cell patients.

Pediatric Cardio-Oncology Medicine: A New Approach in Cardiovascular Care

Survival for pediatric patients diagnosed with cancer has improved significantly. This achievement has been made possible due to new treatment modalities and the incorporation of a systematic multidisciplinary approach for supportive care. Understanding the distinctive cardiovascular characteristics of children undergoing cancer therapies has set the underpinnings to provide comprehensive care before, during, and after the management of cancer. Nonetheless, we acknowledge the challenge to understand the rapid expansion of oncology disciplines. The limited guidelines in pediatric cardio-oncology have motivated us to develop risk-stratification systems to institute surveillance and therapeutic support for this patient population. Here, we describe a collaborative approach to provide wide-ranging cardiovascular care to children and young adults with oncology diseases. Promoting collaboration in pediatric cardio-oncology medicine will ultimately provide excellent quality of care for future generations of patients.

Clinical Utilities of Electrocardiography in the Diagnosis of Myocardial Ischemia in Children With Sickle Cell Anemia: Correlation With Serum Cardiac Troponin I

BACKGROUND

Sickle cell anemia (SCA) is associated with recurrent vaso-occlusive crisis (VOC) and the risk of myocardial ischemia (MI). This study investigated the utility of electrocardiography (ECG) and cardiac troponin I (cTnI) in diagnosing MI during VOC.

MATERIALS AND METHODS

Children with SCA 5 to 15 years of age in VOC (patients) and age-matched and sex-matched steady-state controls were studied. Their ECG and cTnI levels were measured at contact and after 4 to 6 weeks.

RESULTS

One hundred eighty-six children (93 patients and 93 controls) were studied. The mean (SD) ages of the patients and controls were 8.8 (3.2) and 9.0 (3.1) years, respectively. The mean MI score was significantly higher for the patients, 1.7 (1.2), than the controls, 1.3 (1.0), P=0.002. A significantly higher proportion of the patients, 18 (19.4%), also had significant ischemia compared with the controls, 8 (8.6%), P=0.016. The median (interquartile range) serum cTnI level was significantly higher in the patients than the controls, P=0.006. All 7 of the patients with elevated cTnI had VOC. No significant correlation was found between MI score and cTnI in both groups.

CONCLUSIONS

cTnI is elevated and ECG features of MI worsen during VOC. Longitudinal studies to investigate their evolvement over time are advocated.

Sickle cell disease and ventricular myocardial strain: A systematic review

Cardiac disease is the primary cause of death in sickle cell disease (SCD). Cardiac abnormalities begin in childhood and progress throughout life. Right and left ventricular (RV, LV) myocardial strain are early markers of systolic dysfunction but are not well investigated among individuals with SCD. The objectives of this review were to (1) identify all published studies that have evaluated ventricular myocardial strain, (2) summarize their values, and (3) compare findings with those obtained from controls. From search results of four electronic databases-Medline, Embase, Scopus, and Web of Science-42 potential articles were identified, of which 18 articles and 17 studies met eligibility criteria for inclusion. The evaluated studies demonstrate that RV and LV myocardial strain are generally abnormal in individuals with SCD compared with controls, despite having normal ejection/shortening fraction. Myocardial strain has been inconsistently evaluated in this population and should be considered any time an echocardiogram is performed.

Treatment exposures stratify need for echocardiographic screening in asymptomatic long-term survivors of hematopoietic stem cell transplantation

We sought to define the prevalence of echocardiographic abnormalities in long-term survivors of paediatric hematopoietic stem cell transplantation and determine the utility of screening in asymptomatic patients. We analysed echocardiograms performed on survivors who underwent hematopoietic stem cell transplantation from 1982 to 2006. A total of 389 patients were alive in 2017, with 114 having an echocardiogram obtained ⩾5 years post-infusion. A total of 95 patients had echocardiogram performed for routine surveillance. The mean time post-hematopoietic stem cell transplantation was 13 years. Of 95 patients, 77 (82.1%) had ejection fraction measured, and 10/77 (13.0%) had ejection fraction z-scores ⩽-2.0, which is abnormally low. Those patients with abnormal ejection fraction were significantly more likely to have been exposed to anthracyclines or total body irradiation. Among individuals who received neither anthracyclines nor total body irradiation, only 1/31 (3.2%) was found to have an abnormal ejection fraction of 51.4%, z-score -2.73. In the cohort of 77 patients, the negative predictive value of having a normal ejection fraction given no exposure to total body irradiation or anthracyclines was 96.7% at 95% confidence interval (83.3-99.8%). Systolic dysfunction is relatively common in long-term survivors of paediatric hematopoietic stem cell transplantation who have received anthracyclines or total body irradiation. Survivors who are asymptomatic and did not receive radiation or anthracyclines likely do not require surveillance echocardiograms, unless otherwise indicated.